My kids drove our layout. The construction was hurried to get a working line together. We have not finished all the detailing, but it definitely starts to take on something of a life of its own and is a reflection of the kids ideas of what is cool.
I was drug into the hobby reluctantly because of their interest, but it has been great fun. Seeing their personality in the layout has been a neat and unexpected element of the fun.
http://www.youtube.com/watch?v=dbDJDfI7wVE
http://www.youtube.com/watch?v=T5CimnOuK1c